Adjustable wave coupling system



12,, 4 L. NORDE 2,451,444

ADJUSTABLE WAVE COUPLING SYSTEM Filed April 5, 1946 INVENTOR. 1554/5 N020 Patented Got, 12, 1948 ADJUSTABLE WAVE COUPLING SYSTEM Leslie Norde, Hempstead, N. Y., assignor, by to Jefferson Standard Broadcasting Company, a corporation of North iiesne assignments,

Carolina Application April 5, 1946, Serial No. 659,995

1 Claim. (01. 171-119) This invention relates to wave coupling systems and more especially to adjustable inductances for use in such systems.

A principal object of the invention relates to a novel form of transformer in which both the primary and secondary windings are provided with toroidal cores.

Another principal object is to provide an adjustable toroidal core coupling transformer for wave signalling systems and the like, in which the primary and secondary windings can be readily adjusted from maximum to zero coupling coefficients while at the same time preserving sub stantially zero magnetic leakage in all adjusted positions.

A feature of the invention relates to a coupling transformer having toroidal primary and secondary cores, with a common junction core around which both the toroidal cores are rotatable to adjust the coupling coefiicient between the windings on said cores.

Another feature relates to an inductance unit comprising a pair of nested toroidal cores with a common junction core and adjustable means for rotating the plane of one core with respect to that of the other core.

A still further feature relates to the novel organization, arrangement and relative location of parts which cooperate to provide an improved adjustable inductance unit.

Other features and advantages not particularly enumerated will be apparent after a consideration of the following detailed descriptions and the appended claim.

In the drawing,

Fig. 1 is a plan view of one embodiment of the invention.

Fig. 2 is an end view of Fig. i.

Fig. 3 is an enlarged sectional view of Fig. 1, taken along the line 3-3 thereof.

Fig. 4 shows another embodiment of the invention.

Referring to Figs. 1 to 3, there is shown a wave coupling transformer comprising a pair of ringshaped or toroidal magnetic cores H), H. These cores may be of circular cross-section and may be constituted of any magnetic material conventionally used in the manufacture of transformer cores. Preferably however, and particularly where the transformer is to be used in high frequency coupling systems, the cores in and Il are made of compressed comminuted magnetic material such as is conventionally used in so-called permeability tuners. While the drawing shows cores lo and H of the same dimensions, it will be understood that this is done merely for explanatory purposes.

Each of the cores is provided with a circumferential gap with the walls of the gap formed to the arc of a circle. Positioned between each of the cores and passing through the respective gaps therein is a cylindrical auxiliary core l2 also of powdered iron or other magnetic material. The auxiliary core 52 is approximately of the same diameter as the gaps in the respective toroidal cores to and it, so that a relatively close fit exists between the core l2 and the said toroidal cores. However, this fit should be such as to enable either one or both of the cores H] and H to be rotated around the central axis l3-l3 of the core 12.

A suitable winding 54 is provided on core l0, and another winding i5 is provided on core II. The terminals of winding Hi may be connected to any suitable source of electric waves and constitute the primary of the coupling system. Likewise, the terminals of winding l5 are connected to a suitable load circuit and constitute the secondary of the coupling system. The core Iii may be fixedly mounted in a suitable bracket [6 preferably of non-magnetic material so as to maintain the core ii! in a fixed plane. In order to change the coupling coefificient between the primary and secondary, the core II has fastened thereto a shaft i? which may be of insulating material and may carry two contact slip rings l8, l9, to which the terminals of winding l5 are respectively connected. Suitable brushes 2D, 2!, make contact respectively with rings [8 and I9 and these brushes are connected to the desired load circuit.

An adjusting knob or handle 22 is fastened to shaft if, so that by turning handle 22 the planar orientation of core It with respect to core H], can be varied. During this turning of the core l i, no disturbance is effected in the magnetic circuit between the two cores because core I l closely fits around the auxiliary core 12. As a result, the coefficient of coupling between the windings l4 and It can be given any value between zero and maximum, and negligible magnetic leakage occurs during any of the adjusted positions of the core H. With this arrangement, the coemcient of coupling may be continuously adjusted from a given positive value, through zero, to a given negative value. It will be understood of course, that instead of connecting terminals of coil M to one circuit, and the terminals of coil 15 to another circuit, the windings l4 and I5 may be connected electrically in series or electrically in diameter than the toroidal core 24, the cores being mounted in nested relation. The; magnetic circuit between the cores: 2-3 and 2% is; completed by an auxiliar cylindrical core 25. The core 24 with its winding 26 may be attached to any suitable fixed support or bracket which however is arranged so as not to interfere with the'rotation of the core .23 with its winding 2]., The core 23is provided with a suitable bracketiii of nonemagnetic material to which the adjusting shaft, 28 is fastened. By means of the knob 30, the core 23 with its winding 2? can be rotated to assume any planar orientation with respect to the core 24. It will be understood of course thattheter minals of winding 27 are provided with suitable sliprringsand; contact brushes similar to, those shown in Fig. 1. If the core 23 is to bjestationary, then: the; core- Zemay be permanentlyattached t the auxiliary. core 25 and this latter coreli can bedirectly fastened to the: shaft 29 so that by turning knob 39 the planar position of core24 may be varied with respect to core 23.

While certain specific embodiments have been illustrated-,- Various changes and modifications may be made therein without departing from the spirit and-scope of the invention.

What is claimedis:

A variable magnetic core transformer, comprising a first toroidal magnetic core, a second toroidal magnetic core, the second core being of smaller diameter than the first core and located Within the inner periphery of the first core, a magnetic member coupling the two cores to complete a; magnetic circuit therebetween said member being fastened to one core, and passing through the other core to'provide a rotational bearing for said other core as it is rotated, said member being mounted in alignment with the common diameter of both cores to maintain them concentric, each of said cores having a separate magnetizing winding and means to rotate said cores'relatively"toieach other to vary the effective coupling coefficient between said windings. LESLIE NORDE.

REFERENCES CITED The following references are of record in the file of: this' patent:

UNITED S ATES A ENTS" Number Name Date 1,501,649; Cummings July-.15; 192.4 1,,603 822: Wilkinson Oct; 19, 192.6 1,853,548 Casper Apr; 12; L932 2 1625273 Schulze June 1:3;11939 

